Immunohistochemical Expression of Cyclin D1 in Mucoepidermoid and Adenoid Cystic Carcinoma of the Salivary Glands

Background: Cyclin D1 proto-oncogene is an important regulator of (G1 to S) phase progression in many different cell types. The Aims of this study were to evaluate the immunohistochemical expression of Cyclin D1 in mucoepidermoid and adenoid cystic carcinoma of the salivary glands and to correlate the immunoexpression of this protein with the clinicopathological findings. Materials and methods Retrospectively, twelve of archival formalin fixed paraffin embedded tissue samples of salivary Mucoepidermoid and fourteen blocks of adenoid cystic carcinomas obtained from the archives of the department of oral pathology / college of dentistry / Baghdad university, Al-Shaheed Ghazi hospital, were included in this study. Five micrometer sections obtained and immunostained using monoclonal antibody against Cyclin D1. The immunoexpression was detected by the presence of brown stain in the nucleus of tumor cell. The proportion of cells that expressed the stain was correlated with the clinicopathological data of the patients. Results: Cyclin D1 expression was found positive in all cases of MEC and AdCC localized in tumor cells. Nonsignificant statistical relation (p=0.588) was detected regarding Cyclin D1 expression in both types of tumor. Significant relation was found with stage of AdCC (p=0.04) and non-significant concerning other clinicopathological parameters in both tumor types. Conclusion: Weak expression of Cyclin D1 in MEC and AdCC might be explained by Cyclin D1 does not represent an exclusive factor consequently; other factors might be involved in the proliferation, progression and metastasis of both tumor types.